1. Field of the Invention
The present invention relates to a picture display unit, and more specifically, it relates to a picture display unit for displaying pictures on a display by executing picture display processing in accordance with a prescribed program.
2. Background of the Invention
With rapid development of electronic techniques in recent years, a number of electronic game devices, such as "Super Famicon" (trademark) and "Game Boy" (trademark) manufactured and sold by the assignee of the present application, Nintendo Co., Ltd., for example, are now on the market. Such a conventional electronic game device comprises a display such as a CRT display or a liquid display unit, in order to display game pictures which are formed through execution of a game program.
In the conventional electronic game device, control of the play time is entirely left to the player himself. In general, however, the player is too engrossed in the game to wind up in a proper time. In this case, the shoulders, the back, the fingers, the arms and the eyes of the player are disadvantageously fatigued.
Japanese Utility Model Laying-Open No. 3-25923 (1991) discloses an electronic game device which comprises a timer function, in order to prevent children from excess play. However, the electronic game device described in this gazette is so structured as to simply stop the operation after a lapse of a set time, and hence the player must do the game all over again, in order to replay the game. In this case, the player's enjoyment is dampened. Particularly when recent role playing game requiring a long time must be done over every replay, the game cannot be ended for a long time but the play time is disadvantageously cumulatively increased.
The aforementioned problem is not specific to the electronic game device but can also be caused in other picture display units such as a personal computer, an education device etc. which are operated by programs.